I guess this has to do with the communism/ group education.
For a foreigner living in China, it can be really disturbing.
Let me take a few example:
Chinese people don't have any individual space
In China, it is normal to stand close to a total stranger. You can even tap someone on the shoulder, hold someone else arm to attract his attention, to make your point.
In China when you quarrel, you can go so far as to push the person with whom you quarrel
In the west, in case of a verbal quarrel, the limit not to cross is touching the person with whom you quarrel.
In China, in case of a verbal quarrel, you can go so far as to to push the person with whom you quarrel. He will react by pushing you as well! There won't be any fight! Or it would be the exception.
Chinese people didn't have any mailboxes until recently
In the recent past, Chinese people used to live in communities, around some factory for instance. They didn't have mailbox. Someone from the community would distribute the mails.
Today Chinese people have a more individualistic way of life. They have their own mailboxes.
In modern Chinese properties, whenever you come home or go out, you need a magnetic card.
Most Chinese people don't mind. They feel safer this way.